Peristaltic pumps are known and have been utilized in systems for dispensing medical fluid intravenously to a patient. Peristaltic pumps include a normally open fluid flow path, typically defined by a hollow section of tubing, and a plurality of spaced apart “fingers” that sequentially deform the tubing. The sequential deformation of the tubing pressurizes the fluid within the flow cavity and propagates the fluid in a wave-like motion between the inlet and outlet ports of the pump.
While peristaltic pumps have been utilized in the medical art, they are subject to various disadvantages. For example, since the fluid flow cavity is normally open, fluid can be inadvertently supplied to the patient. This can occur if the tubing leading from a source of fluid, such as an IV bag, to the inlet port of the pump is not clamped. Also, the continuous compression of the tubing defining the normally open flow path, can result in tube fatigue, thereby necessitating replacement of the tube that adds to the operational cost of the system.
Peristaltic pumps are affected by the hydraulic head height, resulting from the position of the source of fluid above the pump, which can result in further inaccuracies with the flow rate from the pump. Additionally, peristaltic pumps are typically complex in nature, due to the number of parts required, which is directly related to the cost of the pump.
It is therefore desirable to provide a pump for dispensing medical fluid intravenously to a patient, which overcomes the disadvantages associated with peristaltic pumps.